Safety Assessment of Exit Advance Guide Signs in Mountainous Highway Tunnel Based on Eye-Tracking Technology

Abstract

Exit Advance Guide Signs play an important role in driving safety on highway tunnels. With the increase of mountain highway in recent 10 years, how to set exit advance guide signs inside the mountain highway tunnels become a new problem in China. This paper evaluates the effects of setting schemes of Exit Advance Guide Signs in mountain tunnels through simulation experiments. Specially, exit advance guide signs in the mountainous highway tunnel were divided into location sign and distance sign. Six schemes of different height, width and spacing were tested, in which the distance sign was on the left or right wall of the tunnel, and the vehicle was on the left lane. A Markov chain was used to analyze the driver’s eye movement characteristics to evaluate the effect of separate guide signs. The results were as follows: if the distance sign was set on the left wall, the scheme 4 where height, width and spacing of 1.5m was the best choice, because the change rate of the driver’s pupil area was higher than the threshold, attention to distance signs increased to 10.42%, and dashboard gaze also increased. These characteristics show that the traffic sign setting effect was obvious, and didn’t affect the driver’s driving safety; if the distance sign was set on the right wall, the scheme 6 where height, width and spacing of 2m was the best choice, because drivers pay the highest attention to area 5 and it did not exceed 60%, Meanwhile, the driver’s fixation distribution of scheme 6 was the most stable. This study can optimize exit advance guide signs setting in the mountainous highway tunnel, then contributing to reduced traffic accidents and making mountain highway transport more sustainable.